WiFi issues with DLink DIR-655 routerSupport

I have the DLink DIR-655 router at home and what happens is my Streak seems to time out with the router after going into sleep mode, even though it says its connected in the WiFi menu. I thought a firmware update to the router would do the trick, but to no avail. It's annoying, because after sleep mode I have to turn off and on WiFi again in order for it to work. Anyone know how I can fix this? It's only my router that does this, I never have a problem with the router at work (linksys) or any other routers for that matter.